This invention relates to vibration isolating systems, and more particularly to a suspension system for isolating vibrations of a moving system from the frame on which it is supported.
The problem of isolating vibrations of moving parts has long been recognized, and many solutions have been proposed therefor. While many of the systems which have been evolved have been satisfactory, it has been found most difficult to provide an arrangement which, together with the eliminatioin of undesirable vibrations in the supporting framework of the apparatus, is also economical while at the same time restricting the vibrational movement of the apparatus to a reasonable extent. In addition, it frequently occurs that the moving parts of such apparatus must often be allowed only a certain number of degrees of freedom, and there is thus the problem of absorbing the vibrations between the moving system and the frame while retaining the motion of the moving system within the predetermined limits established usually by the outer cabinet.
As an example of the problems encountered along this line, most automatic washing machines of this type presently commercially available for domestic use provide a clothes basket in which the clothes are washed and rinsed, and when it is desired to remove the liquid from the clothes the basket is rotated at a high speed so as to centrifuge the liquid out of the clothes. Very often, the system for effecting the washing and centrifuging operations does not have its weight symmetrically distributed about the axis of rotation so that there is inherently an unbalance in the system. In addition, the clothes which are being laundered most often will not distribute themselves perfectly about the inner surface of the cylindrical wall of the basket but will provide an additional degree of unbalance. There is the further consideratioin that vibration-caused motion of the moving system must be maintained within reasonable limits, usually on the basis that the supporting frame or cabinet of the machine must be small enough to be commercially attractive for home usage. Yet a further item for consideration is that vertical axis washing machines, that is, washing machines of the type with a basket, open at its top and reached through a lid in the top of the machine, generally should have a highly limited amount of vertical freedom, both from proper functioning of the apparatus itself and again because of the restrictions on size inherent in an appliance which is to be used in the space normally available in most homes.